The invention is based on an apparatus for the gas-treatment and closure of packaging containers as revealed hereinafter. In an apparatus of this kind which has become known from German Offenlegungsschrift No. 24 21 531, for example, the gas supply lines protrude between the container and the foil strip extending toward the container at a flat angle in the direction of the closure device. By disposing the gas supply lines above the central axis of one row of containers, uniform gas distribution is attained if the product settles in the containers such that the surface of the product is level. However, it would also be desirable to have an apparatus with which containers could be closed in a protective-gas atmosphere, for instance those in which portions of the product which are pasty or lumpy and pasty, determined by the filler, have been filled into the container as a pile or stack, the upper part of the pile protruding beyond the opening of the container.